The invention relates to a cleaning device and to a method for cleaning items to be cleaned. Cleaning devices and methods of this kind are employed in various fields in order to apply at least one cleaning fluid to items to be cleaned and thereby to clean said items. Examples of an application of cleaning devices of this kind include dishwashing, both in the private sector and in the commercial sector, and also the cleaning of vessels for receiving human excreta, for example pans, bedpans or similar vessels, or else other types of care utensils, for example for hospitals or care facilities.
Numerous cleaning devices are known which are designed to clean items to be cleaned by means of at least one cleaning fluid. Examples of cleaning devices of this kind are described in DE 10 2004 046 758 A1, in DE 10 2007 053 381 B3 or else in DE 10 2009 035 A1, wherein reference is predominantly made to dishwashers in said documents. Cleaning apparatuses for cleaning pans, bedpans or similar vessels for receiving human excreta are disclosed, for example, in DE 103 48 344 A1. Cleaning apparatuses of this kind are often also called cleaning and disinfection apparatuses.
Cleaning apparatuses such as washers or cleaning and disinfection apparatuses usually have one or more electrical loads. These loads can have, for example, one or more motors or one or more heaters, for example in the form of boilers or flow heaters. Depending on the requirements of the processes being executed, these loads can be switched on individually or in any desired combination, for example in accordance with a program sequence of the cleaning apparatus. Depending on the program sequence, an amount of electrical energy which is sometimes very considerable is required for this.
Accordingly, it is becoming increasingly important to save energy, in particular in the field of commercial dishwashing, but also in the field of cleaning and disinfection apparatuses and also in the domestic field. By way of example, DE 10 2004 046 758 A1 describes a method and an arrangement for operating washers in an energy-saving manner. In this document, a group of electrical load elements of a washer are assigned a maximum total electrical power. An optimum combination of power levels is selected in a requirement determination step, depending on an operating state of the washer, wherein, for each load element of the washer, the selected power level is matched to the power requirement of the load element in the operating state, and wherein the received total power of all of the load elements does not exceed the permissible maximum total electrical power.
DE 10 2007 053 381 B3 discloses a dishwasher having a latent heat store. In this case, a heat recovery device is used, said heat recovery device drawing heat from moist air from a cleaning chamber of the cleaning apparatus and returning said heat to the cleaning apparatus by means of a first cooling fluid. The cleaning apparatus has a cooling fluid line having at least one return path and also at least one heat storage path with at least one latent heat store. The cleaning apparatus is designed to conduct the first cooling fluid to the cleaning chamber and/or into a fluid tank, after it has flowed through the heat recovery device, via the return path in at least one operating state. The cleaning apparatus is further designed to supply the first cooling fluid to the latent heat store via the heat storage path in at least one standby mode.
DE 10 2009 035 668 A1 discloses a cleaning device for cleaning items to be cleaned. The cleaning device comprises at least two loads. The cleaning device has a modular controller which comprises a machine controller and at least one contactless control element. In this case, at least one cleaning program can be carried out, wherein the contactless control element supplies energy to at least one of the loads in a variable manner. The machine controller can provide at least two different drive strategies for the cleaning device, wherein each drive strategy comprises information about energies required by the loads. The machine controller can transmit information about the energies required by the associated loads to the contactless control element via at least one bus system in accordance with a selected drive strategy. The contactless control element can supply the respectively required energy to at least one associated load.
In spite of some advantages which result from the known energy-saving concepts, a considerable amount of current and/or power can be drawn from an electrical power supply system in the building, like before. If, for example, all of the loads are switched on at the same time, the amount of power consumed can be from 3 kW to 12 kW, for example, in conventional batch dishwashers, that is to say commercial dishwashers comprising a stationary washing process. The power consumption is typically a maximum of from 15 kW to 70 kW in conveyor-type dishwashers. The maximum power consumption usually observed in cleaning and disinfection apparatuses when all of the loads are switched on at the same time is from 4 kW to 5 kW.
Electrical feed lines of the cleaning apparatuses have to be designed for maximum occurring levels of electrical power consumption, for example for said values, in the building. In addition, the operator of the cleaning device has to ensure, usually by contractual agreement with his power supplier, that the corresponding power supply and power output is ensured. The costs both of installation in the building and also of the coverage of the power supply contract with the energy supplier generally increase as the level of the maximum consumed power increases. For example, locking systems which are permanently set up and are described in DE 10 2004 046 758 A1 or in DE 10 2009 035 668 A1 are generally able to ensure that not all of the loads are switched on at the same time. Furthermore, a controller of the cleaning apparatus can be set by means of permanently set-up locking systems or else variable locking systems in such a way that the consumed power is allocated to the individual loads in a variable manner depending on requirements. Nevertheless, there is still considerable potential for improvement and optimization, in particular in respect of the high maximum consumed powers. These maximum powers generally result in high costs for the operator, both in terms of electrical installation and also in terms of the contractual arrangements with the corresponding energy suppliers. High maximum powers of this kind are also unfavorable from environmental aspects. Many of the known strategies for limiting the consumed powers naturally also limit the power of the cleaning apparatus in which these strategies are employed.